1. Field of the Invention
The present invention relates to a process for the desulfurization of sulfur-containing hydrocarbon oils. More particularly, it relates to a hydrodesulfurization process wherein a substantially non-metal containing sulfur-bearing hydrocarbon oil is treated with hydrogen and steam in the presence of the hydrodesulfurization catalyst.
2. Description of the Prior Art
Hydrodesulfurization processes in which water as a liquid or as a vapor is added to the hydrodesulfurization reaction zone are known. In the prior art processes, to realize an improvement in the hydrodesulfurization process by the water addition, the hydrocarbon feed treated contained considerable amounts of metallic contaminants such as vanadium and nickel (see for example U.S. Pat. No. 3,753,894) or a substantially metals free hydrocarbon feed could be utilized if the hydrodesulfurization catalyst contained nickel or vanadium (see for example U.S. Pat. No. 3,720,602 and U.S. Pat. No. 3,501,396).
It has now been found that the addition of water will enhance the hydrodesulfurization of a substantially non-metal containing sulfur-bearing hydrocarbon oil utilizing a catalyst which has not been impregnated or composited with a nickel or vanadium component. The term "substantially non-metal containing" as employed in reference to the hydrocarbon feed stream is intended in the specification and claims to define a feed stream containing less than about 80 weight parts per million of metals.